Lloyd Webber had previously announced that a sequel was in the works for the show, which premiered in London in 1986. In fact, at a 50th birthday celebration concert for Lloyd Webber at Royal Albert Hall, a song from that project, "The Heart Is Slow to Learn," was performed by opera diva Kiri Te Kanawa. The plot for the sequel was developed with Frederick Forsyth, author of many books including The Day of the Jackal and The Odessa File. After the composer dropped the project in 1999, Forsyth released the story as a novel, The Phantom of Manhattan. Although Lloyd Webber indicates on his website that he was unhappy with some of the plotting of the novel, his collaboration with Forsyth seems ongoing.
The Phantom of Manhattan novel is set in New York City in the early 1900s and filled with famous characters of the day including Irving Berlin and Teddy Roosevelt. Narrated by a dying Madame Giry, the ballet mistress of the Paris Opera House in The Phantom of the Opera, it tells the story of how The Phantom left Paris after the events of the original story and fled to New York City. There, he becomes a wealthy entrepreneur, building the Manhattan Opera House and luring his Phantom love Christine, now a famous diva, to perform there. Christine is married to Raoul, with a son named Pierre.